According to the DM: Scientists who reviewed the NTP study are asking for the Federal Communications Commission to warn the public, but the FDA's response suggests the findings are over-hyped as it tries to quell consumer's fears.

Some studies have tried to settle the debate over cell radiation. Rates of a particular kind of heart cancer do seem to be connected to greater cell phone usage, but the number of people with rare disease is small.

Scientists have struggled to rule out carcinogenic effects of heat generated by cell phones.

Additional animal studies have found less dire effects at lower cell radiation levels, or more extreme results in small animal studies using high radiation levels.

The result for most of this research has been 'inconclusive' or uncovered 'some' evidence of a link between our cell phones and cancer.

But that research, coupled with a recent study that suggested a link between glioblastomas - the same type of brain tumor that killed Senator John McCain - and cell phone usage was enough for California to issue a warning about the devices.

And since 1999, it has been a concern to the National Institutes of Health (NIH), too, prompting the agency to dedicate $30 million to the NTP to study the link.

In February, those scientists were startled enough by their findings that they issued a warning based on preparatory data: a link between cell phones and cancer was looking likely - though only in some animals.

To see if radiation itself - not heat from cell phones - could cause cancer, they exposed male and female rats and mice to full-body RFR at levels far higher than we experience from our phones.

Some females and some mice developed tumors, but it was mainly male rats exposed to the highest levels of radiation that developed life-threatening cancers.

It's the NIH's job to assess public health trends and risks from environmental factors like radiation and warn us accordingly, and so it did.

But the FDA is responsible for monitoring and ensuring the safety of products, like cell phones, are safe before letting us buy them/

In a statement, the agency assured consumers that it carefully reviews a large body of research and updates its assessments in light of new findings, like the NTP's.

But, 'after reviewing the study, we disagree, however, with the conclusions of their final report regarding “clear evidence” of carcinogenic activity in rodents exposed to radiofrequency energy.'

The FDA was invited to the peer-review process for the NTP study but didn't attend.

Now, it says it will echo the NTP's previous advice to the public, back in February when the preliminary results were revealed.

'These findings should not be applied to human cell phone usage,' it said.

'The totality of the available scientific evidence continues to not support adverse health effects in humans caused by exposures at or under the current radiofrequency energy exposure limits.

We believe the existing safety limits for cell phones remain acceptable for protecting the public health.'

Notably, the NTP study only examined the effects of 2G and 3G radiation. Most phones still contain antennas that can pick up these frequencies, but rely more heavily on newer generation technology like 4G LTE and 5G, which is being rolled out across the US.

Some scientists have warned that 5G - which uses millimeter waves, rather than the microwaves that were the basis of previous generations - may be more dangerous, but it's far too soon to tell for sure.

The FCC is set to auction off radio frequencies to be used for 5G cellular networks on November 14.

While the FDA says that the smart and cell phones we spend hours with every day pass its muster, some experts warn the FCC should pause before the auction day in light of the NTP's final report.

'The US IEEE-FCC human safety guidelines for wireless radiation which only protect against thermal heating or burning were scientifically false decades ago,' said Dr. Paul Heroux, a McGill University physicist and toxicologist.

'The idea that wireless microwaves can only harm the body by heating is ridiculous, as our cells are damaged and impaired in their function before heating.

'The idea that 5G with its more intense millimeter wave radiation emissions will be safe is wrong; it will be quite harmful.'